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  1. GEH will have to stop using the inflated priceing policy that they use whwn selling parts mto operating Nuclear Plants.

  2. 1500MWe ESBWR planned to have 1,132 fuel assemblies and ~38′ core diameter per:


    Using scaling, and making a sketch, it seems like BWRX-300 would have ~224 fuel assemblies with maybe 45 control cells (4 fuel assemblies around a control rod). Nice! that core would be at least 8′ across making BWRX an SMR with fuel economy approaching what we see in the current LWR fleet. So, the BWRX-300 gets my vote as the preferred of all the proposed SMR technology including NuScale. Natural circulation actually makes sense in BWR.

    Still, I pick ABWR over ESBWR because ESBWR gives up the ability to rapidly run-back thermal power by reducing forced convection (re-circulation). ESBWR/BWRX-300 propose modulating feedwater temperature to maintain desired power level between scheduled control rod pattern adjustments. The various recirculation run-backs save a trip every year at plant X. The alternative could be high capacity turbine bypass to a larger condenser?

    GE has a history of selling BWR of whatever vintage in variable diameter; Duane Arnold is about half the diameter of Susquehanna and they are both BWR4.

    The ESBWR and BWRX-300 ARE the future of nuclear – no problem with MOX – 50GWD/T discharge exposure easy. Things have gotten more simple with the fine motion control rods and the natural circulation. GE makes amazing machines!

    1. @michael scarangello

      Interesting analysis.

      This phrase confuses me because it seems out of place in the context of your general approval “Still, I pick ABWR over ESBWR…”

      1. [I can only imagine] There are reasons GE offers both ABWR and ESBWR. The individuals briefly involved in scoping the Wylfa Newydd site in Wales, which unfortunately will not be built, seem to agree that the ABWR might still be the better product. ESBWR gives up a major reactivity control knob (modulating forced convection), ABWR implements what appears to be the ultimate solution to forced convection, under-vessel mounted recirculation pumps. Side note: word is ABWR capacity factor in Japan did not match earlier models prior to the Tsunami – perhaps still in shakedown.

        One additional concept to noodle on: I do not agree with the people that find the incremental approach to nuclear plant design to be flawed. These individuals often say something akin to: “We need to revolutionize the industry with adoption of technology X <>.” The lineage of the BWR stretches back through 6 types that have been built (BWR2/3/4/5/6/A) and projects 1 type that is approved and ready to go (ES) and a further derivative (X) that will not require NuScale-like effort to approve. The lineage stretches back even farther to the BORAX experiments conducted by INL and supported by GE as primary contractor. The incremental evolution of the BWR parallels the incremental evolution of the passenger jet, 707 (BWR2) to A380 (ESBWR). Note that Airbus can’t seem to sell A380s just like GE can’t sell ESBWRs – still Boeing continues to sell the 747 (ABWR). Fly on a 777 and it is not just a dressed-up 757 with WiFi; it is lighter, has more fuel efficient engines, better range – all around better – but still fundamentally the same. Most people (Musk aside) dismiss the revolutionary ideas of Mach2 travel (Concorde = BN600) as simply not worth the risk to operate below the subsonic jet’s economic margins. I digress. Let me assert: we only make good machines after an incremental approach. As Jigar said, we make good cars because we have made millions of them.

      2. This phrase confuses me because it seems out of place in the context of your general approval “Still, I pick ABWR over ESBWR…”

        I think that Michael means that, since the ABWR is still using forced convection, it has direct control over that convection, whereas the newer designs use temperature, which is a more difficult and subtle way of trying to control the same thing.

    2. Correction: ESBWR is 38 fuel assemblies across, which would be about 19′ across. Apologies

      1. BWRX-390 of 19’ is a 5.8m core diameter. To meet the definition used of ‘Small’ for reactor size, as opposed to ‘Small’ reactor electrical power out commonly used, means road shippable which means a max of 4.25m, 4m practical for long items, reactor vessel including full circumference flanges.

        Aside: As far as power output, small is better defined as thermal power, not electrical power because both decay heat and releasable radioactive source term is proportiinal to thermal power and fuel average burnup, not electrical power.

  3. TVA is to use Clinch River site as a location for an SMR demonstration. As TVA shows no interest in the Nuscale modules, expect this GEH unit as a more modest demonstrator.

    My guess.

    1. I agree Clinch River is a more likely site. Clinch River ESP is for up to 700 or 800MWe total, and already has three sites evaluated for SMR LWRs, not just one. Clinch River will also accept Advanced Reactors, i.e., non-LWR, but any delta to the LWR SMR ESP would be needed

  4. This is amusing, because if I recall correctly, the ESBWR was a result of increasing the size and power level of concepts that were originally developed for GE’s SBWR (Simplified Boiling Water Reactor), until the design reached viable economies of scale. (The “E” in ESBWR stands for “Economic.”)

    It’s the same process that resulted in Westinghouse’s AP-1000, which is a bigger cousin of the older AP-600 design. The same thing happened with modular gas-cooled reactors (which I work with) as well: the designers start with a small, modest power level that they know can be easy to cool, and then push the limits to make it bigger and bigger, until the limits of inherent or passive safety are reached.

    Smaller plants are easier to cool

    That is a point that I was trying to make in a recent post here. Yes, small plants greatly reduce the complexity, analysis, and regulatory requirements to ensure that the reactor will not overheat. It also makes the economics more challenging, however.

    It is not surprising that Dominion is participating in the X-300 development. They have long been interested in putting an ESBWR at their North Anna site, but they have never committed to it. Legislation that was passed earlier this year in Virginia might further spur Dominion’s enthusiasm for this design. Power bills will be going up across the state.

    1. Actually, in all other ‘small’ designs except microreactors, the complexities appear to increase significantly compared to ABWR/ESBWR. However, BWRX-300 is vastly simplified compared to ESBWR, in contrast with other SMRs because the basic BWR RPV design hasn’t been redesigned.
      The irony of this being in contrast to the trend of economy of scale isn’t lost on me, but it’s key to recognize it’s the simplification from avoiding the loss-of-coolant accident that enables BWRX-300’s scale and cost reduction, not its mere output size reduction or total power of its shutdown cooling needs.

  5. Excellent high level review of BWRX-300. I fully support BWRX-300 as the most economic LWR SMR. I have even volunteered to help them to get all cooling systems to non-electrical pumping capability as long as there is heat or decay heat > 90C. Also, to extend the passive non-electrical cooling capability to indefinite time as long as water is near by.

    But, since it is still just another rendition of LWR, AND soecifically a derivative of an existing licenses design, does it meet the definition to qualify for the ADVANCED REACTOR Demonstration Program by Congress and the DOE-NE?

    1. BWRX-300 is a dramatic simplification of ESBWR – enabled by designing away the loss-of-coolant accident, the zenith goal of any advanced reactor.
      P.S. And by DOE’s revised definition, any reactor that hasn’t been built basically qualifies as an Advanced Reactor.

  6. There is one massive point missed out from this article, openly stated by Glen Watford, at 47:50, in this video, and that is the 2 year build period. This is the same as any of our low-carbon electricity generating enemies – the renewable technologies.

    It means, the cost-of-capital torture nuclear has had to bear for decades, in this competition, is negated. In the UK, the £587 million capital cost of an NOAK BWRX-300 would would generate 142 million MWh of dividend-paying earnings. £587 million is the capital cost of 527 MW of onshore wind in the UK and that is by far the most cost effective renewable technology. That amount of onshore wind would generate just 31 million MWh.

    Fund managers will be clawing at one another’s throats to get their pension-pot money out of renewables and into the BWRX-300. That exercise in futility so many nuclear supporters advocate – educating the general public – will evapourate. Investment will flow in; politics will follow the money; the 99.99% of the general public – those utterly indifferent to where their energy comes from – will shrug their shoulders and say “just get on with it”:


    1. Where’d you get them rose colored (or coloured) glasses? We should mass produce them like N95 masks and hand sanitizer and distribute to the public free of charge.

  7. How about the siting of this or any of the new nuclear technologies? I remember when I worked at a BWR 3 years ago and read the FSAR that the plant had to be located 40 miles from a major metropolitan area?

    Will the same or similar restriction apply to these new plant? I’m not sure about a unit with 7 days of passive cooling like this one , but it seems as though the units that are passively cooled period, could be sited easier. There are a lot of coal and nuclear plants that have been shut down. It seems like there would be quite an advantage for one of these plants to take advantage of existing sites. A new site would require new substations and transmission lines which can be quite costly.

    The same basic idea applies to the security investment. Would the new units require an army of security people, several manned security stations for the sophisticated security apparatus, sirens and evacuation drills and giant rocks (BFRs) around these plants or a more sensible approach?

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